Running Issues High RPM Nova Engine

[RevvyTrev]

Hello,

I own a 1.3 which i race in Motorsport and seem to be having some issues with high RPM running and am bit stuck on what to check next.

Symptoms
-Struggles to start and idle to begin with
-Can hold throttle down for 5 seconds before it begins to rev fully from cold (once cleared it will rev fine when in neutral)
- Low RPM seems to accelerate fine until then the engine seems to flat line at high RPM and all performance goes. (As if it does not come on cam)
-Once let off after reaching high RPM it backfires


Already Checked
Fuel Pump (Getting power and is pumping)
Plugs removed and cleaned (Was quite oily)
Carb cleaned using carb cleaner. Taken off manifold and flushed.


I am fairly new to working on the engines and a little bit baffled on what direction to head in ?
Could it possibly timing ? or Distributor ? what the best way to check distributor ?

Anybody had this same issues before ?
It was running fine on track. Have put on a trailer left it in a garage for 3 weeks gone to next event after giving the engine a quick clean down with a cloth and some water in a spray bottle. Was careful to keep away from electrics and so on.
Then at the even running issues soon as i fired it.


Regards,

[Andy]

Sounds like it wants setting up properly what carb you running?

[RevvyTrev]

we have to run a Pierberg 20/24.

It was running like a dream prior to parking it in a garage i cant see this being the issue.

[Jonesfach]

we have to run a Pierberg 20/24.

It was running like a dream prior to parking it in a garage i cant see this being the issue.

Have you cleaned the carb jets. A brass wire does the job.
when sitting a while the small holes get clogged up. I don't know where they are on your carb sorry but it's a good place to start. Also is there a fuel filter somewhere that's clogged up?

[mowgli]

Dizzy vacuum advance could be shot.. are you still using it?
How new is the coil?
If you are using big revs, when was the last time the hydraulic lifters were cleaned?

[RevvyTrev]

Its a car used in contact oval racing and I did ping off a concrete wall doing around 50mph 2-3 times . So something could of easily worked loose. I have checked all the electrical connections and they all seem fine.
It is a relatively new car for me with a revamped engine block I am unsure of the age of coils and distributor but both look new.

We do use high revs, I will check the hydraulic lifters tonight and will also run a brass wire in the jets as Jones recommended.

[garyc]

Check to see if the cam belt hasn't jumped a tooth or two.

[Southie]

Check to see if the cam belt hasn't jumped a tooth or two.
This is also what I was going to say but as mowgli said the dizzy advance could be a problem also the dizzy timing could be also out.

Also how tight is your throttle cable through the bulkhead and is it moving freely and smooth to the carb?

[RevvyTrev]

Cam timing had jumped a tooth,

Sorted now thanks guys.